In which of the following situations can you say, without further information, that consumer surplus decreases relative to the market equilibrium level?
a. Your state passes a law that pushes the interest rate (i.e., the price) for payday loans below the equilibrium rate.
b. The federal government enforces a law that raises the price of dairy goods above the equilibrium.
c. Your city passes a local property tax, under which buyers of new houses have to pay an additional 5 percent on top of the purchase price.
d. The government lowers the effective price of food purchases through a food-stamp program.